Who owns BCYC (BCYC)
Which tracked institutional funds hold BCYC, how they are positioned, and who is buying versus exiting — from SEC Form 13F-HR filings. See BCYC company fundamentals →
Ownership as of the 2026-Q1 13F filings. 13F is disclosed up to 45 days after quarter-end, so the most recent quarter fills in over the following weeks.
How the tape is positioned
The tracked-fund tape on BCYC is one-sided between 2025-Q4 and 2026-Q1: 9 added or opened and 34 trimmed or exited — on balance reducing.
A prompt to read the filings, not a verdict. 13F is a quarter-end snapshot disclosed up to 45 days late; a fund adds or exits for mandate, benchmark, and timing reasons that have nothing to do with a view on the stock. This is a starting question, not a signal to trade.
Conviction spread
BCYC’s largest tracked holder by dollar value, BAKER BROS. ADVISORS LP, sizes it at 0.3% of its own reported 13F book, while the median holder sizes it at 0.0% of theirs — a 0.3pp conviction gap — its largest holder concentrates the name more heavily than the typical one.
Book-share is each fund’s reported value in BCYC divided by its whole reported 13F book, so it is comparable across funds of different sizes and is unaffected by stock splits. A higher share means a fund has committed more of its book to the name — a starting question about conviction, not a verdict or a signal to trade.
Institutional & insider positioning
Between 2025-Q4 and 2026-Q1, across 97 tracked filers holding BCYC, 58 increased or opened the position and 42 reduced or closed it; over the same quarter, open-market insider Form 4 buying and selling roughly offset.
This fuses two public signals for the same quarter — how tracked institutions changed their positions and whether insiders bought or sold in the open market. It describes what was filed; it is a starting question, not a verdict or a signal to trade.
New buyers & exits
Funds opening or closing a position in BCYC between the 2025-Q4 and 2026-Q1 13F filings, and the largest changes among funds holding it in both. New buyers and exits are counted on fund presence (split-invariant); adds and trims are measured on reported value.
New buyers 4
- DIADEMA PARTNERS LP$2M
- Qube Research & Technologies Ltd$1M
- Persistent Asset Partners Ltd$559K
- Peapod Lane Capital LLC$550K
Full exits 9
- WESTFIELD CAPITAL MANAGEMENT CO LP$21M
- Candriam S.C.A.$8M
- BNP PARIBAS ASSET MANAGEMENT Holding S.A.$4M
- Jefferies Financial Group Inc.$2M
- TWO SIGMA ADVISERS, LP$1M
- DekaBank Deutsche Girozentrale$801K
Largest adds
- Long Focus Capital Management, LLC$4M
- MARSHALL WACE, LLP$1M
- JANE STREET GROUP, LLC$565K
- RENAISSANCE TECHNOLOGIES LLC$532K
- GOLDMAN SACHS GROUP INC$336K
Largest trims
- BAKER BROS. ADVISORS LP$27M
- FCPM III SERVICES B.V.$8M
- ARMISTICE CAPITAL, LLC$7M
- Siren, L.L.C.$7M
- GSK plc$4M
- PRICE T ROWE ASSOCIATES INC /MD/$4M
Institutional holders
One row per tracked fund, largest reported value first. “% of value” is the fund’s share of this security’s tracked institutional value — not of shares outstanding. Rows marked stale are from an earlier filing than the security’s latest quarter — that fund is absent from the newest snapshot (position exited, or reported under a different name).
| Fund | Shares | Reported value | % of value | Quarter |
|---|---|---|---|---|
| BAKER BROS. ADVISORS LP | 10,885,357 | $51M | 19.5% | 2026-Q1 |
| FCPM III SERVICES B.V. | 3,468,430 | $16M | 6.2% | 2026-Q1 |
| ARMISTICE CAPITAL, LLC added | 3,398,000 | $16M | 6.1% | 2026-Q1 |
| Long Focus Capital Management, LLC added | 3,310,687 | $15M | 5.9% | 2026-Q1 |
| ACADIAN ASSET MANAGEMENT LLC added | 1,968,025 | $9M | 3.5% | 2026-Q1 |
| Siren, L.L.C. trimmed | 1,560,882 | $7M | 2.8% | 2026-Q1 |
| GSK plc | 1,529,561 | $7M | 2.7% | 2026-Q1 |
| PRINCIPAL FINANCIAL GROUP INC added | 1,174,625 | $5M | 2.1% | 2026-Q1 |
| PRICE T ROWE ASSOCIATES INC /MD/ trimmed | 1,028,243 | $5M | 1.8% | 2026-Q1 |
| RENAISSANCE TECHNOLOGIES LLC added | 979,300 | $5M | 1.8% | 2026-Q1 |
| MORGAN STANLEY added | 618,327 | $3M | 1.1% | 2026-Q1 |
| SCHRODER INVESTMENT MANAGEMENT GROUP added | 615,833 | $3M | 1.0% | 2026-Q1 |
| DIADEMA PARTNERS LP new | 476,424 | $2M | 0.9% | 2026-Q1 |
| Birchview Capital, LP added | 463,599 | $2M | 0.8% | 2026-Q1 |
| SILVERCREST ASSET MANAGEMENT GROUP LLC trimmed | 428,684 | $2M | 0.8% | 2026-Q1 |
| CITADEL ADVISORS LLC added | 377,085 | $2M | 0.7% | 2026-Q1 |
| MARSHALL WACE, LLP added | 371,307 | $2M | 0.7% | 2026-Q1 |
| Qube Research & Technologies Ltd added | 308,617 | $1M | 0.6% | 2026-Q1 |
| MILLENNIUM MANAGEMENT LLC trimmed | 283,986 | $1M | 0.5% | 2026-Q1 |
| BlackRock, Inc. trimmed | 278,992 | $1M | 0.5% | 2026-Q1 |
| MOORE CAPITAL MANAGEMENT, LP | 275,000 | $1M | 0.5% | 2026-Q1 |
| Rangeley Capital, LLC added | 232,260 | $1M | 0.4% | 2026-Q1 |
| JANE STREET GROUP, LLC added | 218,115 | $1M | 0.4% | 2026-Q1 |
| Palo Alto Investors LP trimmed | 201,890 | $937K | 0.4% | 2026-Q1 |
| Eversept Partners, LP added | 190,715 | $885K | 0.3% | 2026-Q1 |
| PINNACLE ASSOCIATES LTD trimmed | 185,410 | $860K | 0.3% | 2026-Q1 |
| PLATINUM INVESTMENT MANAGEMENT LTD | 184,603 | $857K | 0.3% | 2026-Q1 |
| FLAX POND CAPITAL, LLC added | 176,136 | $817K | 0.3% | 2026-Q1 |
| TWO SIGMA INVESTMENTS, LP added | 164,800 | $765K | 0.3% | 2026-Q1 |
| Point72 Asset Management, L.P. added | 130,422 | $605K | 0.2% | 2026-Q1 |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | 127,863 | $593K | 0.2% | 2026-Q1 |
| Persistent Asset Partners Ltd new | 120,437 | $559K | 0.2% | 2026-Q1 |
| Peapod Lane Capital LLC new | 121,106 | $550K | 0.2% | 2026-Q1 |
| Marex Group plc added | 115,000 | $534K | 0.2% | 2026-Q1 |
| GOLDMAN SACHS GROUP INC added | 110,147 | $511K | 0.2% | 2026-Q1 |
| XTX Topco Ltd added | 106,392 | $494K | 0.2% | 2026-Q1 |
| TD Asset Management Inc trimmed | 91,992 | $427K | 0.2% | 2026-Q1 |
| ADAR1 Capital Management, LLC added | 71,298 | $331K | 0.1% | 2026-Q1 |
| DAFNA Capital Management LLC | 64,492 | $299K | 0.1% | 2026-Q1 |
| EntryPoint Capital, LLC added | 63,906 | $297K | 0.1% | 2026-Q1 |
| Man Group plc added | 63,305 | $294K | 0.1% | 2026-Q1 |
| AXQ CAPITAL, LP new | 63,134 | $293K | 0.1% | 2026-Q1 |
| State of Tennessee, Department of Treasury | 61,153 | $284K | 0.1% | 2026-Q1 |
| SEI INVESTMENTS CO added | 52,784 | $245K | 0.1% | 2026-Q1 |
| Jump Financial, LLC added | 52,544 | $244K | 0.1% | 2026-Q1 |
| HRT FINANCIAL LP added | 45,915 | $213K | 0.1% | 2026-Q1 |
| ALPS ADVISORS INC trimmed | 40,651 | $189K | 0.1% | 2026-Q1 |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP trimmed | 37,888 | $176K | 0.1% | 2026-Q1 |
| Virtus Investment Advisers, LLC added | 36,601 | $170K | 0.1% | 2026-Q1 |
| Engineers Gate Manager LP added | 35,400 | $164K | 0.1% | 2026-Q1 |
| UBS Group AG added | 32,159 | $149K | 0.1% | 2026-Q1 |
| STATE STREET CORP trimmed | 30,512 | $142K | 0.1% | 2026-Q1 |
| WOODSTOCK CORP | 29,146 | $135K | 0.1% | 2026-Q1 |
| GSA CAPITAL PARTNERS LLP added | 26,842 | $125K | 0.0% | 2026-Q1 |
| Aquatic Capital Management LLC added | 26,160 | $121K | 0.0% | 2026-Q1 |
| GEODE CAPITAL MANAGEMENT, LLC | 25,129 | $117K | 0.0% | 2026-Q1 |
| R Squared Ltd added | 21,057 | $98K | 0.0% | 2026-Q1 |
| State of New Jersey Common Pension Fund D | 20,105 | $93K | 0.0% | 2026-Q1 |
| Vontobel Holding Ltd. added | 20,000 | $93K | 0.0% | 2026-Q1 |
| WESTFIELD CAPITAL MANAGEMENT CO LP added | 3,016,026 | $21M | 8.3% | 2025-Q4 stale |
| RA CAPITAL MANAGEMENT, L.P. | 1,093,477 | $9M | 3.6% | 2025-Q1 stale |
| Candriam S.C.A. added | 1,192,279 | $8M | 3.3% | 2025-Q4 stale |
| Deep Track Capital, LP added | 1,203,244 | $8M | 3.2% | 2025-Q2 stale |
| EcoR1 Capital, LLC | 910,000 | $8M | 3.0% | 2025-Q1 stale |
| TYBOURNE CAPITAL MANAGEMENT (HK) LTD added | 993,743 | $7M | 2.7% | 2025-Q2 stale |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. trimmed | 568,225 | $4M | 1.6% | 2025-Q4 stale |
| Woodline Partners LP trimmed | 362,325 | $3M | 1.0% | 2025-Q2 stale |
| Jefferies Financial Group Inc. trimmed | 297,247 | $2M | 0.8% | 2025-Q4 stale |
| AXA S.A. trimmed | 280,152 | $2M | 0.8% | 2025-Q2 stale |
| Aquilo Capital Management, LLC trimmed | 171,695 | $1M | 0.6% | 2025-Q1 stale |
| Handelsbanken Fonder AB trimmed | 150,000 | $1M | 0.4% | 2025-Q3 stale |
| TWO SIGMA ADVISERS, LP trimmed | 146,100 | $1M | 0.4% | 2025-Q4 stale |
| DekaBank Deutsche Girozentrale | 30,000 | $801K | 0.3% | 2025-Q4 stale |
| Cubist Systematic Strategies, LLC added | 103,410 | $800K | 0.3% | 2025-Q3 stale |
| Walleye Capital LLC added | 111,659 | $791K | 0.3% | 2025-Q4 stale |
| Janney Montgomery Scott LLC new | 100,291 | $697K | 0.3% | 2025-Q2 stale |
| Soleus Capital Management, L.P. added | 100,000 | $695K | 0.3% | 2025-Q2 stale |
| Caption Management, LLC trimmed | 81,559 | $692K | 0.3% | 2025-Q1 stale |
| BANK OF AMERICA CORP /DE/ trimmed | 96,401 | $683K | 0.3% | 2025-Q4 stale |
| MONIMUS CAPITAL MANAGEMENT, LP added | 93,840 | $664K | 0.3% | 2025-Q4 stale |
| Shay Capital LLC new | 60,000 | $509K | 0.2% | 2025-Q1 stale |
| Nan Fung Group Holdings Ltd | 68,943 | $488K | 0.2% | 2025-Q4 stale |
| Quadrature Capital Ltd added | 46,728 | $331K | 0.1% | 2025-Q4 stale |
| Skandinaviska Enskilda Banken AB (publ) | 42,729 | $297K | 0.1% | 2025-Q2 stale |
| HARBOR CAPITAL ADVISORS, INC. trimmed | 40,486 | $287K | 0.1% | 2025-Q4 stale |
| Paloma Partners Management Co new | 39,250 | $273K | 0.1% | 2025-Q2 stale |
| Dynamic Technology Lab Private Ltd trimmed | 27,959 | $216K | 0.1% | 2025-Q3 stale |
| UBS AM, A DISTINCT BUSINESS UNIT OF UBS ASSET MANAGEMENT AMERICAS LLC added | 27,300 | $190K | 0.1% | 2025-Q2 stale |
| D. E. Shaw & Co., Inc. new | 21,548 | $153K | 0.1% | 2025-Q4 stale |
| SIMPLEX TRADING, LLC added | 19,986 | $142K | 0.1% | 2025-Q4 stale |
| FOX RUN MANAGEMENT, L.L.C. new | 19,771 | $140K | 0.1% | 2025-Q4 stale |
| AMERIPRISE FINANCIAL INC added | 14,972 | $116K | 0.0% | 2025-Q3 stale |
| EXCHANGE TRADED CONCEPTS, LLC added | 12,764 | $108K | 0.0% | 2025-Q1 stale |
| ENVESTNET ASSET MANAGEMENT INC trimmed | 12,420 | $105K | 0.0% | 2025-Q1 stale |
| Squarepoint Ops LLC added | 13,259 | $103K | 0.0% | 2025-Q3 stale |
| PNC Financial Services Group, Inc. added | 14,138 | $100K | 0.0% | 2025-Q4 stale |
| Graham Capital Management, L.P. trimmed | 12,375 | $96K | 0.0% | 2025-Q3 stale |
| Vanguard Personalized Indexing Management, LLC trimmed | 12,776 | $90K | 0.0% | 2025-Q4 stale |
| TOCQUEVILLE ASSET MANAGEMENT L.P. added | 12,600 | $89K | 0.0% | 2025-Q4 stale |
| RAYMOND JAMES FINANCIAL INC added | 12,336 | $87K | 0.0% | 2025-Q4 stale |
Ownership over time
Tracked institutional holder count and total shares held by filing quarter (independent scales). The curated-era tail and any mid-ingest latest quarter are handled honestly — a partial quarter is not drawn as a collapse.
Reading this table
Funds hold the same stock for different reasons — an index fund “holds” almost everything, an active manager sizes a name to a mandate and a benchmark, and each fund entered at its own price and time. Because 13F is filed up to 45 days after quarter-end, every row is a backward-looking snapshot; a manager may have traded since. Share-class siblings (a company’s A and C shares) are rolled up to one line so a dual-class name is never double-counted. Compare like-for-like. A large holder is not an endorsement, and a fund exiting is not a warning — this is a starting question, not a verdict.
About 13F filings
A Form 13F is a quarterly disclosure that institutional investment managers with over $100 million in US-listed equities must file with the SEC. In plain English: it is a snapshot of the long stock positions a fund held at the end of a quarter. It covers long US-listed equities only — not short positions, options, cash, or private holdings — and the funds shown are the large sample we track, not the complete 13F universe.